scholarly journals Physiological and pharmacological inductors of HSP70 enhance the antioxidative defense mechanisms of the liver and pancreas in diabetic rats

2018 ◽  
Vol 96 (2) ◽  
pp. 158-164 ◽  
Author(s):  
Maja Dimitrovska ◽  
Mirsada Dervisevik ◽  
Natasa Cipanovska ◽  
Katerina Gerazova ◽  
Suzana Dinevska-Kjovkarovska ◽  
...  

Heat preconditioning (HP) is a powerful adaptive and protective phenomenon and the heat stress proteins (HSPs) it produces are an important determinant for the development of diabetic complications. Aspirin has been reported to modulate heat shock response in different organisms through increased induction of HSPs and is also known to exert antioxidative and radical scavenging effects in diabetes. We estimated the effect of physiological (heat stress: 45 min at 41 ± 0.5 °C) and pharmacological (aspirin treatment) induction of HSP70 on several parameters of oxidative state in the pancreas and liver of diabetic rats. Diabetes increased HSP70 level and decreased poly(ADP) ribose polymerase (PARP), glutathione (GSH), and glutathione peroxidase (GPx) activities in the pancreas. In the liver, there was reduction of HSP70 level, GSH concentration, and CAT activity, while GPx and GR activity were enhanced. HP of diabetic rats caused an additional increase of HSP70, GSH, and antioxidant enzymes in both organs. Pre-treatment of HP–diabetic animals with aspirin led to an additional increase of PARP and HSP70. Both HP and aspirin, as physiological and pharmacological inductors of HSP70, respectively, enhanced the antioxidative defense mechanisms of the liver and pancreas in diabetic rats.

Author(s):  
CAYSANDRA AUDREY MICHELLE ELWON ◽  
MUHAMMAD DAWOOD SHAH ◽  
MOHAMMAD IQBAL

Objective: The present study was designed to demonstrate the antioxidant, hypolipidemic and hypoglycaemic potentials of aqueous extract of O. corymbosa against alloxan-induced diabetes in rats. Methods: O. corymbosa extract was tested for phytochemical screening, total phenolic, flavonoids content and DPPH free radical scavenging activity. Diabetes was induced in Sprague Dawley rats by administration of alloxan monohydrate (65 mg/kg b. w i. v). The aqueous extract of O. corymbosa at a dose of 100 mg/kg and 200 mg/kg were administered through gavage feeding daily to diabetic induced rats for 14 d. The effect of aqueous extract of O. corymbosa was assessed on blood glucose, body weight, lipid peroxidation, catalase activity, glutathione and lipid profile. Pancreatic tissues were also examined by haematoxylin and eosin staining methods. Results: Phytochemical screening shows the presence of tannins, saponins, phlobatannins and flavonoids. Total phenolic content was found to be 22.85±0.21 mg/g, IC50 is 450±1.39 µg/ml and total flavonoids content was found to be 4.25±0.09 mg/g of extract. The results of the present study showed that O. corymbosa can lower blood glucose and lipid parameters except for HDL. The levels of antioxidant enzymes CAT and GSH were increased along with the decreased in LPO level by the pre-treatment of animals with O. corymbosa. Microscopic examination of pancreatic sections revealed that diabetic rats treated with O. corymbosa extracts at either dose have normal architecture structure of islets. Conclusion: These results indicate that O. corymbosa may be effective as a hypoglycaemic and antihyperlipidemic agent.


2019 ◽  
Vol 19 (3) ◽  
pp. 292-301
Author(s):  
Omar Farid ◽  
Naoufel Ali Zeggwagh ◽  
Fadwa EL Ouadi ◽  
Mohamed Eddouks

Objective: The aim of this work was to evaluate the antihyperglycemic activity of aerial parts aqueous extract (A.P.A.E) of Mentha pulegium (M. pulegium) on blood glucose levels in normal and streptozotocin(STZ)-induced diabetic rat. The glucose tolerance was evaluated in normal rats. Moreover, the histological sections and morphometric analysis at the liver and pancreas have been carried out in this investigation both in normal and STZ-diabetic rats. Methods: The effect of A.P.A.E of M. pulegium (20 mg/kg) on blood glucose levels was investigated in normal and diabetic rats (n=6). Histopathological changes in liver and pancreas were examined under phase contrast microscope and a preliminary screening for various bioactive constituents was realized according to standard methods. Key Findings: Both single and repeated oral administration of A.P.A.E (20 mg/kg) caused a significant reduction in blood glucose levels in STZ-diabetic rats (p<0.0001). The morphometric analysis and histological sections realized in pancreas and liver have showed the beneficial effect of the A.P.A.E in cellular population. According to oral glucose tolerance test (OGTT), the aqueous extract has revealed an improvement of glucose tolerance in normal rat. Furthermore, the preliminary phytochemical screening of A.P.A.E of M. pulegium has demonstrated the presence of various metabolite compounds including polyphenols, flavonoids, terpenoids tannins, cyanidins, sesquiterpenes, and glycosides. Conclusion: We conclude that the A.P.A.E of M. pulegium (20 mg/kg) exhibits a potent antihyperglycemic activity in STZ diabetic rats.


Antioxidants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 51
Author(s):  
So-Eun Kim ◽  
Chan-Ju Lee ◽  
Sul-U Park ◽  
Ye-Hoon Lim ◽  
Woo Sung Park ◽  
...  

Carotenoids function as photosynthetic accessory pigments, antioxidants, and vitamin A precursors. We recently showed that transgenic sweetpotato calli overexpressing the mutant sweetpotato (Ipomoea batatas [L.] Lam) Orange gene (IbOr-R96H), which carries a single nucleotide polymorphism responsible for Arg to His substitution at amino acid position 96, exhibited dramatically higher carotenoid content and abiotic stress tolerance than calli overexpressing the wild-type IbOr gene (IbOr-WT). In this study, we generated transgenic sweetpotato plants overexpressing IbOr-R96H under the control of the cauliflower mosaic virus (CaMV) 35S promoter via Agrobacterium-mediated transformation. The total carotenoid contents of IbOr-R96H storage roots (light-orange flesh) and IbOr-WT storage roots (light-yellow flesh) were 5.4–19.6 and 3.2-fold higher, respectively, than those of non-transgenic (NT) storage roots (white flesh). The β-carotene content of IbOr-R96H storage roots was up to 186.2-fold higher than that of NT storage roots. In addition, IbOr-R96H plants showed greater tolerance to heat stress (47 °C) than NT and IbOr-WT plants, possibly because of higher DPPH radical scavenging activity and ABA contents. These results indicate that IbOr-R96H is a promising strategy for developing new sweetpotato cultivars with improved carotenoid contents and heat stress tolerance.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Karima Bensiameur-Touati ◽  
Ghouti Kacimi ◽  
El-Mehdi Haffaf ◽  
Sihem Berdja ◽  
Souhila Aouichat-Bouguerra

Context. Nigella sativa seeds are usually used as traditional medicine for a wide range of therapeutic purposes. Objective. To investigate the subacute toxicity of NS aqueous extract and select its lowest dose to study its antidiabetic effect. Methods. 5 AqE.NS doses (2, 6.4, 21, 33, and 60 g/Kg) were daily administered to mice by gavage. Biochemical parameters measurements and histological study of the liver and the kidney were performed after 6 weeks of supplementation. Thereafter, and after inducing diabetes by alloxan, rats were treated by 2 g/Kg of AqE.NS during 8 weeks. Metabolic parameters were measured on sera. A horizontal electrophoresis of plasmatic lipoprotein was conducted. Glycogen, total lipids, and triglycerides were measured in the liver. TBARS were evaluated on adipose tissue, liver, and pancreas. Results. AqE.NS showed no variation in urea and albumin at the 5 doses, but hepatotoxicity from 21 g/Kg was confirmed by histopathological observations of the liver. In diabetic rats, AqE.NS significantly decreased glycemia, TG, T-cholesterol, LDL-c, and TBARS and showed a restored insulinemia and a significant increase in HDL-c. Results on the liver indicated a decrease in lipids and a possible glycogenogenesis. Conclusion. AqE.NS showed its safety at low doses and its evident antihyperglycemic, antihyperlipidemic, and antioxidant effect.


2007 ◽  
Vol 85 (3) ◽  
pp. 362-371 ◽  
Author(s):  
Martine Liberge ◽  
Roxane-M. Barthélémy

Immunohistochemical methods were applied in the present study to investigate the expression of stress proteins such as metallothioneins (MT), which are metal-binding proteins, and heat shock proteins (Hsp70), as well as an antioxidant enzyme (superoxide dismutase, SOD), in the freshwater crustacean copepod Hemidiaptomus roubaui (Richard, 1888) exposed to cadmium or heat stress. The results show a tissue-specific distribution of MT-like protein after cadmium exposure in the brain and in the nerve cord. Cadmium stress did not provoke inducible Hsp70 or SOD expression. Unlike cadmium, heat stress induced the expression of Hsp70 and SOD in the shell glands, a structure involved in the reproductive function, and more particularly in the formation of the diapause egg envelope. MT expression is not induced in animals exposed to heat stress.


2021 ◽  
Vol 1 (2) ◽  
pp. 1-8
Author(s):  
Abubakar A. Yusuf ◽  
Toheeb D. Yissa ◽  
Abdulhakeem Rotimi Agboola ◽  
Sodiq M Balogun ◽  
Peter O. Adeboye ◽  
...  

Background: The prevalence of diabetes mellitus is increasing on a global trend. The aim of the present study is to identify the most effective antioxidants and hypoglycemic fraction of Azanza garckeana. Methods: The fractions (nhexane or ethyl-acetate or aqueous) of A. garckeana were administered to the alloxan-induced diabetic rats at doses of 100, 200, and 400 mg/kg for 15 days. Antioxidants activities were evaluated at concentrations of 62.5, 125, 250, and 500 µg/mL using the DPPH scavenging assay. Results: Results revealed that both the hexane, ethyl-acetate, and aqueous fractions exhibited hypoglycemic and antioxidants activities in a dose-dependent manner. The n-hexane fraction demonstrated highest percentage DPPH scavenging effect of 26.34±3.43, 38.44±4.35, 59.34±3.45, and 74.83±5.35 at 62.5, 125, 250, and 500 µg/mL respectively. The ethyl-acetate fraction demonstrated 19.33±2.98, 28.94±3.24, 47.34±2.90, and 57.82±4.54 respectively while the aqueous fraction exhibited the least activities of 12.45±23.45, 18.64±2.94, 27.94±3.89, and 39.43±3.89 at concentrations of 62.5, 125, 250, and 500 µg/mL respectively. In addition, the n-hexane fraction demonstrated the most significant hypoglycemic effect with the highest glucose reduction of 58.97 ±3.45 %, 63.86±5.35 %, and 66.51±4.35 %, ethyl acetate fraction demonstrated glucose reduction of 7.55±0.54%, 21.77±2.35 %, and 29.56±3.46 % while the aqueous fraction demonstrated the least hypoglycemic effect of 9.89±2.67 %, 18.09±3.45 %, and 18.87±3.24 at 100, 200 and 400 mg/kg bw respectively. Conclusion: The n-hexane fraction of Azanza garckeana extract could serve as a reservoir of bioactive agents that could be useful for the development of a new anti-diabetic agent


Author(s):  
Nithya R ◽  
Subramanian S

Objective: This study was aimed to evaluate the antioxidant potential of sinapic acid in both in vitro and in vivo. Recently, we have reported that oral administration of sinapic acid (3,5-dimethoxy 4-hydroxycinnamic acid) an active phyto ingredient widely distributed in rye, mustard, berries, and vegetables has been shown to ameliorate hyperglycemia.Methods: Experimental Type 2 diabetes was induced in male Wistar rats by feeding high-fat diet to induce insulin resistance followed by intraperitoneal administration of a single low dose streptozotocin (35 mg/kg body weight [bw]). Sinapic acid was administered orally at a concentration of 25 mg/kg bw/rat/day for 30 days, and its efficacy was compared with metformin. In vitro, antioxidant scavenging properties of sinapic acid were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide, and nitric oxide (NO) assay.Results: Sinapic acid treatment showed a significant decline in the levels of lipid peroxides, hydroperoxides and protein carbonyls in the plasma and vital tissues of diabetic rats. The treatment also improved the antioxidant status in diabetic rats indicating the antioxidant potential of sinapic acid. In addition, the results of DPPH, ABTS, superoxide, and NO radical scavenging assays substantiate the free radical scavenging efficacy of sinapic acid.Conclusion: The results of this study evidenced that sinapic acid possess significant antioxidant properties which in turn may be responsible for its antidiabetic properties.


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